Qt 5.6 LTS 3 yeays

原文: http://blog.qt.io/blog/2015/12/18/introducing-long-term-support/
With Qt 5.6 we are introducing the first Long Term Supported (LTS) release of the Qt 5 series. There will be several Qt 5.6.x patch level releases created during the next three years – also after the next Qt 5.x releases
become available. Commercial licensees eligible for technical support will also be able to submit support requests longer for the LTS release.

Current LTS release has been Qt 4.8, and with its support ending at the end of 2015, it is time to introduce the next LTS release. Qt 5.0.0 was released three years ago and we have done a huge
amount of improvements since then, as well as provided many good and widely used releases. Thanks to recent improvements in our releasing infrastructure we now have a sustainable way of developing parallel Qt releases with different sets of supported platforms
and compilers.

As our LTS promise, we guarantee that Qt 5.6 will be supported for three years via standard support, after which additional extended support can be purchased. During this time period, even though following Qt releases (5.7 onwards)
are already out, Qt 5.6 will receive patch releases providing bug fixes and security updates. Typically we have provided just one or two patch level releases for each Qt 5.x release, and this is planned to continue also in the future for the non-LTS releases.
For Qt 5.6 LTS release the amount of patch releases will be higher, as we aim to provide these throughout the three year period.

With Qt 5.6 we will also roll out a change to the commercial support terms and conditions to recognize LTS versions of Qt, with the three year standard support period. At the same time we are reducing the standard support on
non-LTS releases of Qt to be one year. There will be an option to purchase extended support for both LTS and non-LTS releases. The changed support terms do not affect already released Qt 5.x releases, these are supported two years from the release of next
Qt version, as defined in the current support terms.

In addition to security fixes, error corrections and improvements provided by the LTS patch releases, we may also add support for new operating system and compiler versions to an LTS release of Qt, when possible. It should be
noted that the deprecated modules and technology preview modules are not subject to the LTS.

We had a strong focus on improving quality and providing feature parity between different platforms with Qt 5.5, for example in multimedia and connectivity areas, and have continued to improve further in Qt 5.6. Our aim is to
provide a solid baseline with support for C++98 and C++11 compilers, just like before. The next release, Qt 5.7, will drop support for older compilers allowing us to leverage C++11 functionality in the Qt modules themselves. So for those wishing to use compilers
such as VS2008, VS2010, and gcc 4.6, Qt 5.6 continues to be an excellent choice in the years to come.

The
Qt 5.6 Beta release is now available, check it out if you have not yet done so. We are working hard to further fix and polish it with the target of having the Qt 5.6.0 final out in Q1/2016.